Security readout for executives and security teams
Plain-English summary
CVE-2021-34349 is a high-severity command injection flaw in QNAP QVR. A remote attacker with high privileges could run arbitrary commands on an affected QNAP device. QNAP says the issue is fixed in QVR 5.1.5 build 20210803 and later.
Executive priority
Treat as a prompt patching item for any QNAP QVR deployment, especially where administrative services are remotely reachable. Business urgency is reduced by the high-privilege requirement, but impact is severe if compromised.
Technical view
The vulnerability is classified as CWE-78 command injection in QNAP QVR. CVSS 3.1 is 7.2: network reachable, low attack complexity, high privileges required, no user interaction, unchanged scope, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to QNAP devices running QVR versions earlier than QVR 5.1.5 build 20210803. The source bundle does not provide a precise affected version range or CPE list.
Exploitation context
The provided sources do not report active exploitation, and the CVE is not marked CISA KEV. The CVSS vector indicates exploitation requires authenticated high privileges, but could be performed remotely without user interaction.
Researcher notes
Public details are sparse. The bundle confirms command injection and the fixed QVR build, but not the vulnerable endpoint, affected version range, exploit maturity, or indicators of compromise. Avoid assuming unauthenticated exploitation.
Mitigation direction
- Update QVR to 5.1.5 build 20210803 or later.
- Inventory QNAP devices running QVR across the environment.
- Restrict QVR and QNAP administration access to trusted networks and users.
- Review QNAP advisory QSA-21-35 for any current vendor guidance.
Validation and detection
- Confirm each QNAP QVR installation version and build number.
- Verify QVR is at least 5.1.5 build 20210803.
- Check whether QVR or QNAP admin services are internet reachable.
- Review QNAP logs for unusual privileged activity where available.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-78: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-34349 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.2 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H1.25.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.2HighVector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.qnap.com/en/security-advisory/qsa-21-35CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.